Mutations in introns give rise to cystic fibrosis, breast cancer or forms of anemia.

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In March, NICE ruled against the use of two drugs, Lapatinib and Sutent, that prolong the life of those with certain forms of breast and stomach cancer.

WSJ: Of NICE and Men

He said PARP-inhibitors might also be good for treating other forms of breast cancer that behave in a similar way, which account for a fifth of all breast tumours.

BBC: Image of breast cancer

And then there are those annual lifetime caps that insurance companies set, where once you go over that cap -- as many women do because some forms of breast cancer are so expensive to treat -- then that cap makes it impossible to pay a penny more for that treatment.

WHITEHOUSE: The First Lady and Dr. Jill Biden Observe Breast Cancer Awareness Month | The White House

At Glenfield Hospital, in Leicester, staff were able to remove a three-week delay in breast cancer waiting times by re-designing their patient registration forms.

BBC: Cancer waiting times cut

So far, targeted drugs have produced dramatic advances for only a few less-common forms, including leukemia, certain stomach tumors and a subset of breast cancers.

FORBES: Conquering Cancer